my encounter with a ghost

I was in my room watching videos and I was seven at the time. I wanted to go see what my brother what was he doing.  So I went down the main hall and in his room. I slowly opened the door and I saw him talking to a ghost. It was a tall man he looked like in his 50s he was just sitting there with my brother I was kinda freaked out. My brother looked at me and said “ um is everything okay “ after he said that the man was gone. We moved out but something told me why was that man with my brother.